Created question in FIWARE Q/A platform on 10-06-2022 at 14:06
Please, ANSWER this question AT https://stackoverflow.com/questions/72575722/fiware-orion-mongodb-docker

Question:
FIWARE ORION MONGODB DOCKER

Description:
I want to set up my raspberry pi3 as a MQTT publisher(JSON data), here is the code:
import json
import random
import time

import paho.mqtt.client as mqtt

THE_BROKER = ""
THE_TOPIC = ""
CLIENT_ID = ""

1. The callback for when the client receives a CONNACK response from the server.
   def on_connect(client, userdata, flags, rc):
   print("Connected to ", client._host, "port: ", client._port)
   print("Flags: ", flags, "returned code: ", rc)

1. The callback for when a message is published.
   def on_publish(client, userdata, mid):
   print("sipub: msg published (mid={})".format(mid))

client = mqtt.Client(client_id=CLIENT_ID,
clean_session=True,
userdata=None,
protocol=mqtt.MQTTv311,
transport="tcp")

client.on_connect = on_connect
client.on_publish = on_publish

client.username_pw_set("", password=None)
client.connect(THE_BROKER, port=1883, keepalive=60)

client.loop_start()

while True:
s = {}
s['the_variable'] = random.randint(0,100)
j = json.dumps(s)

msg_to_be_sent = j
print(j)
client.publish(THE_TOPIC,
payload=msg_to_be_sent,
qos=0,
retain=False)

time.sleep(15)

client.loop_stop()

And i want to use Orion ,MongoDB that are running on the Docker as a subscriber, here is the code:
import json
import time
import sys
import struct
import paho.mqtt.client as mqtt

THE_BROKER = ""
THE_TOPIC = ""
CLIENT_ID = ""

1. The callback for when the client receives a CONNACK response from the server.
   def on_connect(client, userdata, flags, rc):
   print("Connected to ", client._host, "port: ", client._port)
   print("Flags: ", flags, "returned code: ", rc)

client.subscribe(THE_TOPIC, qos=0)

1. The callback for when a message is received from the server.
   def on_message(client, userdata, msg):
   print("sisub: msg received with topic: {} and payload: {}".format(msg.topic, str(msg.payload)))

client = mqtt.Client(client_id=CLIENT_ID,
clean_session=True,
userdata=None,
protocol=mqtt.MQTTv311,
transport="tcp")

client.on_connect = on_connect
client.on_message = on_message

client.username_pw_set(None, password=None)
client.connect(THE_BROKER, port=1883, keepalive=60)

1. Blocking call that processes network traffic, dispatches callbacks and
2. handles reconnecting.
   client.loop_forever()

First question, How can I add a mqtt-subscriber to the Orion?
Second question, yes I need to set up a broker(mosquitto will be used), how can i generate JSON data as a publisher? That are sending data in JSON format in every 30 seconds? I need your help!
Thank you very much for your help!!!